A printer has a direct printing function which directly prints image data or print data stored in the memory card connected to the printer, without assistance of a host device such as personal computers (e.g., see JP-A-2003-326773)
Memory cards have been sufficiently reduced in size for easy portability. Users can carry a memory card so that they can connect it to a printer having the direct printing function to view print data for work or image data of photographs at any time. Thus, users can readily print and view document by only connecting the memory card to a printer having the direct printing function without the assistance of a host device.
Additionally, a printer having the direct printing function also has a screen display function for displaying a reduced image and a file name of each piece of data on a liquid crystal display, and an index-printing function for printing a list of reduced image and a file name of each piece of data. Therefore, users can selectively print image data or print data stored in a memory card.
Each piece of data may be stored in the memory card with a certain level of security so as not to be manipulated by others than a user who created the data. The security for such data have multiple levels, e.g., a security for prohibiting only printing of data, a security for prohibiting only viewing of data, and a security for prohibiting both printing and viewing of data.
When users connect a memory card, which contains data with security, to a printer and select the screen display function or the index printing function, data with the security for prohibiting printing would be prohibited from being printed, or data with the security for prohibiting viewing would be prohibited from being displayed by the displaying function.
However, assuming that the users have selected the screen display function, for example, and data (file information) is stored in the memory card (storage device) with a level of security (restrictive information) for permitting viewing of data but prohibiting printing of data, reduced images of the data or the file names are displayed on the liquid crystal display even though printing of the data is prohibited. Users visually identify the contents displayed on the liquid crystal display to determine whether to execute printing of the data. Therefore, the users would be misled into believing that the data prohibited from being printed could be printed since the reduced images or file names are displayed even though printing of the data is prohibited.
Additionally, the users who were misled into believing that the data prohibited from being printed could be printed may try to print the data that is actually prohibited from being printed. This would result in printing of the data not being executed or only blank paper coming out from the printer even when the printing has been executed. Thus, even though the users tried to print the data, the users cannot print it as desired, thereby impairing the usability of the printer (printer apparatus).